Fastening device



Jan. 3, 1939. E. J. mp 2,142,925

FASTENING DEVICE Filed Dec. 6, 1937 INVEN'IOR Q. EDWARD TALES TRIPP V A ATTmNE' 's Patented Jan. 3, 1939 UNITED STATES PATENT OFFHCE FASTENING DEVICE Application December 6, 1937, Serial No. 178,372 In Great Britain December 9, 1936 12 Claims.

This invention relates to an improved fastening device for the attachment of doors, panels, aircraft cowlings and other coverings to framework or other structural parts, so that such coverings may be rapidly and efficiently detached therefrom and attached thereto.

In the specification of my British Letters Patent No. 361,963, I have described and claimed a fastening device in which a latch body in the form of a casing adapted to extend plug-like into a socket or equivalent staple member contains a plunger carrying locking arms spring influenced to tend to extend through lateral openings in the casing into engagement with the staple member to secure the latch body thereto, the plunger being slidable axially in the casing in the direction in which it extends into the staple member to retract said locking arms against their spring influence, and in the opposite direction to allow said arms to move under their spring influence to extend through the lateral openings in the casing. In the fastening device more particularly described in said specification, the locking arms are attached pivotally to the plunger to rock about axes transversely of the latter from positions in which they extend away rom the free end and longitudinally of the plunger, to positions in which they extend outwardly through the lateral openings in the casing; the edges of said locking arms being so shaped as to co-operate cam-fashion with the margins of the corresponding lateral openings in the casing to effect their retraction and extension through said openings.

The improved fastening device according to the present invention comprises a casing which is attachable to a door or other covering, a plunger movable axially within said casing and spring influenced to extend outwardly, and a 49 latch or locking arm which is retracted and extended through an opening in the casing to its unlocked and locked position by the inner end of said latch or of an attachment thereto cooperating with one or more surfaces on the plunger and/or on the casing which are inclined obliquely to the direction of movement of the plunger, so that when the said plunger is pressed inwardly into the casing, the latch is retracted within the casing, and, on release of the plunger, returns to its locking position.

In the present preferred form of the invention, the latch or locking arm is secured to a pin or cross-piece which extends transversely of said plunger and whose ends extend through slots in arms or walls of the plunger and engage in slots or grooves in walls of the casing, the said slots or grooves in the casing inclining inwardly away from said opening and transversely to the slots in the plunger which are so disposed that parts thereof register with the slots or grooves in the casing for the various axial positions or" the plunger.

One form of fastening device in accordance with this invention is illustrated in the accompanying drawing, in which Figure l is a side elevation of the fastening device showing one mode of attachment to aircraft cowling,

Figure 2 is a sectional view of the fastening device, showing another mode of attachment to aircraft cowling,

Figure 3 is a top plan view of the fastening device,

Figure 4 is a bottom plan View thereof, and

Figure 5 is a vertical sectional view to an enlarged scale, showing the device with the latch fully retracted.

Referring to the drawing, the fasteningdevice comprises the casing I which is open at both ends and which is provided at its outer end with a flange 2 whereby it may be secured to a door, aircraft cowling or other covering, the said flange 2 being suitably formed with holes 3 for this purpose. Movable axially within the casing i is a plunger which comprises the head portion l which slidably fits the casing i, and two opposed operating walls or arms 5, which are provided with suitably inclined slots or apertures d to cause movement as hereinafter described the pin 6 which extends transversely of the said plunger and which has pivotally mounted thereon a latch or locking arm I that is urged to extend laterally into locking position through the aperture 8 provided in a Wall l of the casing l. Helical springs 5! formed with extensions, of which one, i l, is anchored to the head portion i of the plunger, act to urge the plunger outwardly and thereby the latch or locking arm outwardly to its locking position. The other extension of the springs H engages the inner end or the latch 1, thereby urging the latch inwardly against the inner edge of the opening The ends of the pin 6 engage in slots iii which are formed in the walls of the casing adjacent the wall I and which extend transversely to the slots 50 9. The slots H3 incline inwardly away from the wall l of the casing, so that when the plunger is depressed against the action of the springs H which are thereby tensioned, the pin 6 is forced inwardly by the outer edge of the slots 9 to bear against the inner edge of the slots l0 and to move therein away from the side i of the casing, the latch 1 being thereby drawn out of engagenient with the latch plate or other member with which it engages to fasten the door or other covering. It will be seen that the latch or locking arm moves in a direction which is substantially at right angles to the direction of movement of the plunger. 7 e

A transverselyrextending slot lz or lnteriorlydisposed: groove may be suitably formed in the side of the casing opposite the side i so that,

when the latch is fully retracted, the adjacent g plunger, it is given a small pivetal mot the reverse direction to bring the ed e of the head [of the plunger clear of the slot l2, user:

the springs ll return the latch and plunger to the position in which the; latch is fully ex ndedh In this position, the head 4 of the plunger is, shown, preferably flush with the flange 2 7 c casing. To facilitate pivotal movement of the plunger of the thumb or finger of the e head 4 thereof may be provided with a y asishown Figures 2 and 4. r

The casing of the fastening device may extend plug-like into a socket or equivalent staple member secured to the framework or other structural part to which the door or other covering is to be removably secured, the ;outer edge of the latch or locking arm, when in its locking position, abutting against an inneieedge ofthe socket and thus locking the door or like covering. For example, as shown in Figure 2, the casing whose flange 2 is secured to cowling I 4, extends plug+ like into the socket l5 which is fitted into a bracket lfi that is secured to the framework it, It will be seen that any action tending to draw apart the attached parts when the latch in its locking position does not result in any tendency for the latch to retract out of engagement with the socket l5. Alternatively, the latch of the fastening device may engage directly an abutment on the structural part to which the covering is to be attached. For example, as shown in Figure 1', the flange 2 of the casing i lay be secured to cowling'll, the latch 1 extending through and engaging directly an edge of an aperture in the structural part l8 to hold securely such part IB'to the cewling M. The fastening device, being free from parts substantially projecting beyond the exterior surface of the part to which it is attached, is particularly applicable to the'attachment of eowling, inspection doors and other coverings in aircraft/ 4 The inner and outer sides of the latch 1 advantageously converge towards its outer end, the outer side of the latch preferably being parallel or substantially parallel to the flange, as shown. In this manner, when the latch moves to its looking position, the outer side thereof moves towards the flange on the casing, thus drawing tightly together the two parts to be attached.

It will be understood that variations in the constructional details of the fastening device above described may be made in accordance with this invention. For example, a plurality of latches may be secured t9 the pin 6, and the angles of inclination of the slots may be varied. Furthermore, slots inclined to the direction of movement of the plunger may beformed only in the plunger or in the casing. For example, the pin to which the latchis secured may extend through slots in the plunger which extend at right angles to the directfon of movement of the plunger, the ends of the pin engaging inclinedislots in the casing, or the pin may extend through inclined slots in the plunger, the slots in the casing with which the end of the pin en gages extending laterally.

I claim: i

l. A fasteningldevice comprising a casing having an opening in a side thereof, a plunger mounted *within said casing and movable longitudinally therein, a pin extending transversely of said planger, a latch secured at an inner part thereof to said pin and adapted to extend through said opening, and pooperating surfaces on said plunger and casing engaged by said pin and operable to move said pin away from said openingwhen the plunger is moved towards one end of said casing and thereby retract the latch through said opening 2. A fastening device comprising a casing having opposed side walls and a front wall with an opening therein, a plunger formed with opposed side walls mounted Within saidgcasing and movable longitudinally of said casing, a spring urge ing the plunger towards one end. of said casing, a pin extending transversely of said plunger, as latch secured at an inner part thereof to said {in and adapted to extend through said opening, and cooperating surfaces on the opposed' walls of the plunger and casing engaged by said pin,

at least one pair 'of said co-operating surfaces being cam surfaces operable to move said pin away from said opening when the plunger is moved longitudinally of said casing against: the action of said spring and thereby retract the latch through said opening. I

3. A fastening device according to claim 2, wherein said (lo-operating surfaces are formed by slots in the opposed Walls of the plunger and easing, said pin extending through the slots in said walls of the plunger and engagingthe slots in the said walls of the casing;

4. A'fastenin'g device according to claim 2, wherein said surfaces on the opposed walls of the plunger are formed by slots therein which are inclined obliquely to the direction of movement of said plunger.

5. A fastening device comprisinga casing having opposed side walls and a front wall formed with an opening therein, a' plunger formed with opposed side walls mounted within said cas ng with such side walls extending substantially parallel to the said casing side Walls, a spring urging the plunger towards the outer end of said casing, a pin which extends transversely of said plunger, a latch secured at its inner end to said pin and adapted to extend through said opening, and co-operating slots in the opposed walls of the plunger and of the casing, said pin extending through the slots in the plunger walls and engaging the slots in the casing side walls. at least one pair of Said. co-operating slots being cam slots operable to move said pin away from said opening when the plunger is moved inwardly of the casing and thereby retract the latch through said opening.

6. A fastening device according to claim 5, wherein said slots in the plunger side walls extend obliquely to the direction of movement of said plunger, and the co-operating slots in said casing side walls extend obliquely to the direction of movement of said plunger and transversely of the slots in said plunger walls.

'7. A fastening device according to claim 5, wherein said latch is pivotally secured to said pin and said spring is housed within the plunger and engages both the plunger and the latch, whereby the plunger is urged outwardly of said casing and the latch is urged against the inner edge of said opening.

8. A fastening device according to claim 5, wherein said casing is formed with a rear wall having an abutment surface, and said spring is housed within said plunger and acts both to urge the plunger outwardly of said casing and, on depression of the plunger to the position in which the latch is retracted, to urge part of the plunger into engagement with said abutment and thereby hold the plunger in said position.

9. A fastening device comprising a casing having opposed side; walls and a front wall formed with an opening therein, a plunger formed with opposed side Walls mounted within said casing with its said side walls extending substantially parallel to the casing side walls, slots in the opposed walls of said plunger inclined obliquely to the direction of movement of said plunger, a pin extending transversely of said plunger with its end portions extending through the oblique slots in the plunger walls, a latch p-ivo-tally secured at its inner part to said pin, and surfaces. on said opposed side walls of the casing engaged by said end portions of the pin and co-operating with said slots in the plunger walls to move the pin away from said opening when the plunger is moved inwardly of said casing and thereby retract the latch through said opening,

10. A fastening device comprising a casing having an opening in a side thereof, av plunger formed with opposed arms movable axially within said casing, a pin extending transversely of said plunger, a latch pivotally secured to said pin and adapted to extend through said opening, a spring housed between said plunger arms and acting both to urge the plunger outwardly of the casing and to urge the latch against the inner edge of said opening, and co-operating surfaces on said plunger and casing engaged by said pin and operable to move the pin away from said opening when the plunger is pressed inwardly of the casing and thereby retract the latch through said opening.

11. A fastening device according to claim 10, wherein said casing is formed with a transverse slot and said spring also acts to pivot the plunger about the said pin to bring part of the plunger into engagement with said transverse slot when the plunger is moved inwardly of the casing to a position in which the latch is fully retracted and thereby hold the plunger in such position.

12. A fastening device according to claim 10, wherein the inner and outer sides of said latch converge towards the outer end thereof, and the outer end of said casing is formed with an outwardly-extending lateral projection which cooperates with said latch when the latch is extended through said opening, to draw together parts to be attached.

EDWARD JAMES TRIPP. 

